3.5 Anxiolytics and Hypnotics Flashcards
What happens in REM and slow wave sleep?
slow wave - memories during the day are reactivated during this sleep REM - LOW AMPLITUDE ACTIVITY - very fast oscillations - consolidation of sleep - to strengthen memories
In which brain region does SWS occur?
Hippocampus and neocortex Reactivation Short term memory
In which brain region does REM occur?
Cortex Consolidation in long term stores
What is the function of the suprachiasmatic nucleus?
Circadian pacemaker - It controls many circadian rhythms in the body - It receives in puts from phostosensitive neurones in the retina
What does the suprachiasmatic nucleus activate?
The suprachasmatic nucleus activates the dorsal medial hypothalamic nuclues which in turn activates the monoamine cell body regions. These are the origins of the ascending arousal pathways which project to the cerebral cortex to induce consciousness.
Which areas in the brain cause wakefulness?
Excitatory monoamine pathways, with cell bodies in midbrain that project to the forebrain and it’s the release of these excitatory neurotransmitters in the forebrain that cause wakeful ness and they includen the raphe nuclei which release 5-HT etc.
What is the mechanism of sleep?
At night time the pineal gland produces melatonin to selectivity inhibit the scn, so therefore the dorsomedial hypothalamic neuclus no longer receives input and therefore stops activating the monoamine pathways Inhibits suprachiastmic nucleus - inhibits arousal pathways
In addition GABA and galanine are released from the VLPO and inhibit the neurones in these regions and therefore decrease release in projection areas to reduce arousal. Targeted inhibition.
Also worth noting that GABA all over brain and there will be GABA released from interneurons onto the neurones postsynaptic to the monoaminergic projections
What is insomnia?
Poor sleep, not just number of hours but also quality
What are the different types of insomnia?
Initial insomnia, stuggling to get to sleep
Middle insomnia, is when you keep waking up
Terminal insomnia when you wake up early.
Why is insomnia more common in the elderly?
↑ Prevalence elderly less melatonin being relased, obviously incraese in other illnesses that can affect sleep
Daytime drowsiness, irritability, ↑ accidents, ↓ productivity = ↓ quality of working/personal life
What are the causes of insomnia?
- Stress
- Psychiatric illnesses
- anxiety - initial
- depression - terminal
- bipolar - sws
- PTSD - less REM
- Medical Illness
- Alzheimer’s, asthma, rheumatoid arthritis
- Medications and drugs
Why does stress interfere with sleep?
Also the stress hormone cortisol itself will interfere with sleep. The release of cortisol also follow a circadian rhythym and fall at night time so having heightened stress hormone levels will interferr with the process of sleep.
Also cortisol has been shown to block the flow of activity between the hippocampus and neocortex thus interfering with laying down memories in longer term stores and also intefering with ltp which is needed to strenthen synapses
What factors would make up an ideal hypnotic?
a) inhibit arousal pathways
b) not affect other brain regions
c) short half life
d) no side-effects
What are the different types of anxiety disorders?
- Panic disorder with or without agoraphobia
- Agoraphobia without panic disorder
- Generalised anxiety disorders
- Persistent anxiety/worry > 6 months
- Obsessive compulsive disorders
- Counteracted by compulsive behaviour (rituals) which provide temporary relief
- Social anxiety disorders
- Post traumatic stress disorder
What is the acute effect of SSRIs on anxiety?
Increased serotonin then increased anxiety
